


runs in the family

by nilchance



Series: lest ye be judged [6]
Category: Undertale (Video Game)
Genre: Gen, Post-Undertale Pacifist Route, that awkward moment where all your adoptive siblings have tried to murder you
Language: English
Status: Completed
Published: 2017-06-02
Updated: 2017-06-02
Packaged: 2018-11-07 22:23:04
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 3,308
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11068317
Author URL: https://archiveofourown.org/users/nilchance/pseuds/nilchance
Summary: Sibling bonding: results may vary.





	1. flowey

It’s strange to be able to walk into the ruins. Sans has stood outside that huge, heavy door so many times, telling jokes, that it feels wrong to see it standing open. He could’ve teleported into the place before now, but it belonged to the old lady and that’d just be goddamn _rude_. He wasn’t raised in a barn.  
   
It was mostly alleys. Totally different set of etiquette.  
   
The ruins are lonely. There’s a deep pool of quiet inside now that the froggits and moldsmals have migrated aboveground. All those years Tori spent in here, alone… it’s no wonder she seems so happy with her little crowded house in the suburbs.  
   
He doesn’t make the effort to be quiet. He knows where he’s going, and he doesn’t want to startle the person waiting there. That’d be a stupid way to die.  
   
When he gets to the little patch of flowers, Flowey doesn’t raise his head. Instead, like he’s said it a billion times and expects to do it a billion more, he says, “Don’t you have anything better to do, Frisk?”  
   
"Today they do," Sans says.  
   
Flowey whips around so fast that it's amazing his roots don't tear. The way he sneers almost hides that he's scared. Sans pretends that’s not satisfying. "Look at this. A trashbag grew legs! What do you want? To gloat?"  
   
Sans ambles closer, like his soul isn't screaming at the idea of coming anywhere near this fucking thing. He can still feel his spine cracking under chokehold vines. "Believe it or not, I didn't come to give you a hard time."  
   
Flowey scoffs. "You're an idiot if you think I'm gonna believe you about anything."  
   
"Guess that's the root of the problem, huh, bud?"  
   
"Ugh. No wonder your stupid brother complained about your puns all the time. He really lost his head over them!" Flowey laughs. "How's that for funny? Or how about the fact that you stood back and watched him die?"  
   
Sans wobbles his hand back and forth: _so-so_. "I guess you'd know all about that, huh, Asriel."  
   
Flowey goes very still. Watchful. It's like Sans has him by the stem and is putting pressure on, ready to pull him out of the ground.  
   
"I get it," Flowey says. "You've been talking to Frisk. I bet they told you allll about it. Poor sad weak little Asriel, stuck underground being lonely. I thought _you_ knew better, but I guess you're even stupider than Frisk. Asriel's dead."  
   
"Yep. Dusted. Gone. Totally didn't show up, take everybody’s souls and then beg for forgiveness. Must've been some other dead prince."  
   
For a heartbeat, it's like there's a filter over the world, Flowey's face layered with one with soft eyes and floppy ears. Toriel's ears, Asgore's eyes. Then Flowey shuts down, goes surly and mean. "That crybaby isn't here anymore. Good riddance. If you want to talk to him, you better ask Frisk to reset. Then you can die over and over and _over_ , just like old times! Won't that be fun?"  
   
"Laugh a minute." Sans studies him. "No soul, no emotion, no love, huh. That why you don't want your folks finding out who you used to be? Because I gotta level with you, that sounds suspiciously like you give a damn."  
   
"I don't care," Flowey says. "I just don't want the fuss. They'd come down here and snivel all over me and want me to be somebody else. It's bad enough that Frisk shows up. So what? Are you gonna tattle on me?"  
   
"Turns out I agree with you."  
   
"You wanna lie and keep people in the dark? Careful or I'm gonna die again of surprise."  
   
Admittedly, it's predictable. Plus there's the little fact that Flowey remembers the resets whereas Sans only got the shitty highlight reel of deja vu and flash judgment. Who knows how many times they've had this conversation?  
   
When Sans doesn’t bother answering, Flowey huffs out an annoyed breath. "Then why are you here? You must want something real bad if you're actually doing things."  
   
Sans pulls the prepaid cell phone out of his hoodie pocket and tosses it onto the bed of flowers. Flowey darts under the ground. The phone makes no sound when it hits, pollen fluffing up to hang in the lazy sunlight like dust.  
   
When nothing explodes, Flowey slowly pokes his head up and glowers. "What the heck is this?"  
   
"What's it look like?" Sans asks, managing not to add _now who's the idiot?_ It's like he's an adult. "It's a really high tech banana."  
   
Squinting at him, Flowey prods the phone with one of his vines. It turns on, and he startles but doesn't smash it. Reluctant interest creeps onto his face.  
   
"Why?" Flowey asks finally.  
   
"You kill people when you're bored," Sans says. "Try Candy Crush instead. It'll be great."  
   
Flowey's expression twists. His mood swings like a child’s. "You know what I did. I'm not sorry."  
   
"Turns out murdering everyone kind of goes past sending you to your room to think about what you did."  
   
"You could always try to kill me," Flowey says. "The whole bad time routine. My favorite part is where you say 'Papyrus, do you want anything?' and die."  
   
"For somebody who doesn't care, you're trying real hard to piss me off." When Flowey opens his mouth, Sans cuts him off. "Frisk forgave you. Now all you've got is sulking and trying to screw with people’s heads. You lost. Sucks to be you."  
   
Vines begin to rattle. Flowey tries to loom, but compared to the last few times he’s tried to kill Frisk, it’s lackluster. "Don't you dare _pity_ me, comedian!"  
   
"Heh." Pity? No. Sans thinks he’s been there. (He doesn’t know for sure. He almost never does.) Clutching a cell phone on his brother's grave, trapped in the underground. Calling his enemy because they're the only one who could almost understand. He tries not to pity himself these days. "The phone was Frisk's idea."  
   
Not entirely a lie. Frisk wants to save everyone, and they'd lit up when Sans told them about the phone. Frisk had been the one who installed all the games and books, and it's Frisk who Flowey can text or e-mail or hit up on a dozen social media sites at any hour. It's Frisk who's holding their heart out here.  
   
(Papyrus's number is in the contacts, too. Sans is trying not to freak out about that and not entirely managing.)  
   
And because it's Frisk, Flowey hesitates.  
   
"They're such an idiot," Flowey grumbles finally, and puts the phone down. He keeps it real close.  
   
"A total sap," Sans agrees. When Flowey growls, Sans gives him a nod. That's about as much togetherness as he can take today. Looking at Flowey hurts his head after a while, because the judge doesn't know what to make of him.  
   
Flowey is a murderer with a damn good excuse. He’s also a victim, a dead kid who trusted their sibling and paid for it, whose sad story doesn't balance the scales at all. It was simpler when Sans hated him, before he got too tired to hate anything anymore.  
   
"Seeya," Sans says, and turns on his heel.  
   
He almost gets to the door when Flowey calls out, "Wait."  
   
Sans waits. When Flowey doesn't say anything, he looks over his shoulder at him. "What? I've got a whole lot of nothing to do today."  
   
Flowey fidgets, in as much as a flower can. "Aren’t you gonna kill me?  
   
Like it's never occurred to Sans. Like they've never killed each other before.  Like Flowey is worth the trouble.  
   
"Nah," Sans says, and doesn't add _and fuck you for even asking._  
   
See? Adulthood.  
   
Some of the fight bleeds from Flowey. He looks small and his sneer is tired. "Then tell Frisk not to come back here."  
   
"I do," Sans says. "Every time. It doesn't stick."  
   
"I don't want to see them."  
   
"You really think it matters what you want?"  
   
Surly, Flowey glares at the ground. "If they come back, I'll hurt them."  
   
"Azzy, pal, friend-o, you're gonna hurt them whether they come around or not. That's family for you." Sans gives Asgore’s son a mock salute. "Besides, you're gonna want somebody to change your ringtone."  
   
"What?" Flowey demands, sounding genuinely alarmed. "What does that mean?"  
   
Sans walks out with the last word. Before he's even to the door, he hears the tinny strains of _Build Me Up Buttercup_ followed by a scream of impotent rage.  
   
Grinning, he takes the shortcut home.


	2. frisk

   
Frisk finds Sans on Toriel’s back porch, eating Grillby’s takeout and watching the sunset. Sans gives them a lazy wave as Frisk thumps down onto the step beside him.   
   
There's dirt on their bony little knees, under their nails, a long smudge of it up their cheek. Sans can already see the exasperated look on Toriel's face. Like she doesn't love fussing over Frisk every chance she gets.  
   
"Leave any dirt for the flowers?" Sans asks, and holds out his box of fries. They're always hungry lately. Growth spurt.  
   
Frisk takes three fries and stuffs them in their mouth. Hands thus freed, they sign, _apple trees this time. We planted them behind the school. Dad says hello._  
   
Sometimes Sans wonders how much Frisk knows. He doesn't think he's told them the truth about Asgore, not when he hasn't even told Papyrus. Just in case, he tries not to look like that casual little 'dad' felt like a kick in the chest.  
   
"Makes sense," Sans says. "It is an elemen-tree school."  
   
Frisk laughs and holds out their closed fist, so he bumps it with his own. _It'll be there when students get stumped._  
   
What a great kid. Sans offers them the fries again.  
   
They fall into a companionable quiet. Another great thing about Frisk: they don't talk, and so they don't feel the need to fill the silence. They can just sit and chill. Watch a sunset or two.  
   
It's gotten darker when Sans speaks up in the relative safety of the shadows. If he’s gonna be honest, it’s easier if Frisk can’t really see him. "Hey, uh. Just... be careful around Asgore."  
   
Frisk turns to frown at him. Protective.  
   
"He's a good guy," Sans says. "He's not gonna hurt you. But he might not be there one day. That's all."  
   
When Sans closes his eyes, he still hears the sound of Asgore tearing out his own soul. From the look in Frisk's eyes, they remember it too. They swallow hard and look away.  
   
Sans sighs. "Or hell, maybe I don't know what I'm talking about. Forget it."  
   
Maybe things'll be different this time.  
   
Frisk leans against his side. Feeling like absolute garbage, Sans puts his arm around them. Frisk signs, _You're right. But he's still my dad._  
   
"Listen. He's gonna try as hard as he can for you, okay?" When Frisk nods, he adds, "And there's a lot of people who love you, pal. You can count on somebody always being around. Toriel, Undyne, Papyrus..."  
   
Frisk turns towards him. _And you?_  
   
"Heh." It's Sans's turn to look away. The backyard lights click on, startling. Feeling him flinch, Frisk burrows tighter into him. "You know I ain't exactly reliable either, Frisk."  
   
Frisk moves out from under his arm so they can look him in the face as they sign, emphatic, _I trust you._  
   
Sans opens his mouth, then shuts it. They look ready to fight him if he argues. They'll fight mercifully, kindly, but there's no budging Frisk when it comes to one of their people.  
   
When did Sans become one of Frisk's people?   
   
As soon as they met, probably. Frisk has a habit of making the whole world their problem. The real question is when did Frisk go from an anomaly to be placated and resented to one of Sans's people?  
   
Ha. People, hell. Somehow this little jerk snuck in under all the barbed wire fences and screaming alarms. They're family.  
   
Frisk grabs his hand in their own. No words, but Sans catches their drift.  
   
The poignancy of the moment is kind of killed by the fact that he had a whoopee cushion up his sleeve. Frisk pauses in the aftermath of a truly righteous fart noise. Then the two of them start snickering.  
   
"Jeez, kid," Sans says, "I'll give your compliments to Grillby."  
   
Extricating their hand, Frisk signs, _Emergency whoopee cushion?_  
   
"Sure. Gotta be prepared. What if I meet an ambassador or something?"  
   
The ambassador in question grins. _I want one._  
   
"Hey, good thing you know a guy." Sans shoves his sleeve up and takes off the whoopee cushion. "That'll be 50g."  
   
Frisk checks their pockets, then shakes their head. They're still smiling.  
   
"Yeah, okay. 49g." Sans winks. "Friends and family discount."


	3. chara

   
There is no stone over Chara's grave. The humans like to do that, because they've got enough space up there to forget where they left corpses. Seems like a funny thing to forget, but what does Sans know. Monsters only leave dust, and by definition dust gets everywhere.  
   
It's strange, standing over the little patch of buttercups and knowing there are bones underneath. Like Asgore planted a seed but all it yielded was grief and a seriously ugly divorce.  
   
"So." Awkwardly, Sans scratches his brow. The dead kid isn’t going to start this conversation. "Fancy meeting you here. Thought I should come and say hi. Considering, uh. Stuff."  
   
Asgore, he means. The stories Asgore told him about Chara and Asriel when he was a kid. The sense of kinship that Sans knows damn well is only in his own head even while it dragged him down here.  
   
Sans sighs. "Yeah, okay, you got me. It's not just to check in and say hi. I got a question for you. Wanna hear it?"  
   
If the kid isn't interested enough to answer, they're also not pissed off enough to pull a poltergeist routine. Good enough for Sans.  
   
"I died." The words fall bluntly into the uninterrupted quiet. "Your mom and dad died. Everybody did, once or twice, but here we all are. Even Asriel's alive again. Seems like death doesn't stick like it used to. So. Here's my question: are you still dead?"  
   
The quiet is profound. The flowers are blooming, but the birds aren't singing. No ghosts whisper in his ear. No dramatic flash of lightning, no breeze ruffling the flowers. Zilch.  
   
"Welp. That's a real shame. There are some folks who'd love to see you. I get it, though. Sometimes you're just too fu-- frigging tired."  
   
He pulls the packet of glow-in-the-dark stars out of his pocket. "Anyway, seeing as I made the trip and all, I'm gonna put these up on the ceiling. Probably gets boring down there. Maybe you wanna look at something different."  
   
When he talks to Gaster, there's a sense of listening. Of interest. Chara's giving him nothing.  
   
Then again, Chara killed themself. Hopefully the poor damn kid isn't still around. They paid a lot to get some peace.  
   
"All right, kid," Sans says. "Prepare to be dazzled. I'm sirius. When I'm done with this ceiling, it's gonna be stellar."  
   
One upside to Chara being dead: they're a tolerant audience.  
 

****

   
 _Why are you going to the ruins?_ Frisk asks.  
   
Sans looks up from the battered copy of Restaurant at the End of the Universe to study them. They stare back at him, too serious for a little kid tucked in their bed. It’s late, and after two chapters he’d kind of figured the kid was drowsing. They’d certainly been quiet enough.  
   
He puts the book down on its face, because its spine is beyond broken at this point. Toriel would scold him if she saw. “Just keeping an eye out,” he winks the good eye, “for your bud-dy down there.”  
   
They shake their head, solemn. _That’s not the only reason._  
   
Sans leans back against the headboard. “Yeah? How do you figure?”  
   
They glance away, frowning down at the bedspread with its pattern of trees. _Because Flowey,_ they use a namesign, the letter F and a circle around the face like the sign for ‘sad’, _was watching you. He saw you at the grave._  
   
They’re lying. He can’t tell why. “Your mom doesn’t get there as much as she wants. I can check in easier than she can and make sure the moldsmals haven’t dripped on it again.”  
   
 _You talked to them,_ Frisk signs. _You shouldn’t do that._  
   
A chill creeps over Sans’s bones. He shrugs it off. “Seemed rude to stand on them without saying hi first.”  
   
The light of their bedside lamp is kind and golden. There’s no reason for Frisk’s eyes to glint red. _You said their name. If you say something’s name, it might answer. Do you understand?_  
   
Golden light. Red eyes. Red on the blade. Dusty hands.  
   
What if it wasn’t just Frisk with him in that hallway?  
   
What a handy scapegoat. What an easy thing to blame. The devil made Frisk do it? No. He’s had to come to terms with the fact that the kid he loves is the same kid who killed Papyrus. He’s dealt with it. He knows.  
   
Sans is sweating, his hands buzzing with power that wants to wake up. When Frisk doesn’t move, hardly seems to breathe, Sans takes a deep breath for them. Then another. With a calm he’s really, really not feeling, he says, “Yeah. I hear you.”  
   
Their hands move jerkily, like they’re puppeting from a long way away. _They just want to be left alone. They’re tired._  
   
“I know the feeling. Well, they can get their beauty sleep. I won’t bug them anymore.”  
   
Slowly, Frisk nods. The two of them sit in awful quiet for a moment, until Sans realizes that Frisk is starting to shiver. He reaches out to tug the blankets around them, then stops and says carefully, “You with me, buddy?”  
   
Frisk sniffs and nods again, more fluidly this time. Like an actual kid and not… whatever that was. Sans gives up on the blankets and just hauls them into his arms instead. For all that they’re taller than him now, they suddenly feel too little.  
   
Into their messy hair, he says, “I’m sorry.” He isn’t sure who he’s apologizing to.  
   
After a while, Frisk gives a jaw-cracking yawn. Sans lets them go so they can huddle back beneath the blankets. They still look pale, but they’re heavy-eyed now. Exhausted. He rubs his hand over their head until their hair sticks straight up. “You gonna be okay? I can get Toriel.”  
   
The kid shouldn’t have to deal with this alone. They’re 10, they don’t even know fractions. Dead people should be way above their paygrade. It doesn’t matter that they killed some of those people themself.  
   
They shake their head and give him a (fake) smile. Hopefully they didn’t pick that habit up from him. _Will you read another chapter? I like it when you do the voices._  
   
He starts fingercombing the hair back down. Fur and bone, he gets, but hair is still weird to him. At least Frisk seems to find it comforting. Humans like to be petted almost as much as dogs, apparently.  
   
“I can do that,” he says. He’s still got to head home to read to Papyrus and he’s got work in the morning, but fuck it. At this point he’d give the kid a kidney. He doesn’t even have one of those, but he’d go find one if they never spook him like that again.  
   
Reading his worry, they pat his arm. _They’re not going to hurt anybody. They’re just not ready yet._  
   
Yet. That word falls between them like a brick. Sans swallows. “That’s… great. Tell ‘em they can take their time.”  
   
Frisk smiles up at him, already half-asleep. _I don’t have to. They’re listening._  
   
Frisk is out within a page. Sans doesn’t sleep at all that night. 


End file.
